The present invention relates to a process for producing magnetic metallic oxide.
Soft magnetic oxide is generally represented by the general fundamental formula of M.sup.2+ O.Fe.sub.2 O.sub.3, where M.sup.2+ signifies Fe, Mn, Ni, Cu, Mg, Zn or Co, part of which can be substituted by other metal. Since magnetic oxide which exhibits advantageous magnetic properties may be produced in a combination of these divalent metals, the oxide may be produced by suitably selecting the metals so as to match its utility.
It is reported that there is a process for synthesizing magnetic oxide of this fundamental formula. The synthesis employs as a starting material any of the oxides of the above metals and/or salts, of the above metals in a solution. It is also reported that ferrite is synthesized from a ferro-manganese alloy by dissolving ferro-manganese in hydrochloric acid and then adding any of the oxides of the above-mentioned metals to the solution. On the other hand, the present invention provides a novel process for producing magnetic metallic oxide which can be stably and inexpensively synthesized by employing ferro alloy, metals such as electrolytic zinc, alloys, oxide such as the oxides of Fe, Mn, Ni, Cu, Mg, Zn or Co or salts of Fe, Mn, Ni, Cu, Mg, Zn or Co which become oxides by heating without anisotropy.
It is ordinarily difficult to synthesize excellent ferro alloy by pulverizing ferro alloy, electrolytic iron, electrolytic manganese or electrolytic zinc and adding other metallic divalent oxide to produce the ferrite. Because, when these metals and alloys are pulverized and are oxidized by atomizing melted alloy, there exists a danger of an explosion occuring, the oxides of the metals or the alloys thereby obtained have a low activity and are segregated in the alloy. Accordingly, its local anisotropy becomes large in the magnetic oxide, which thus becomes non-homogeneous. This is mainly because adequate powder cannot be obtained due to the toughness and ductility of the ferro alloy or electrolytic metal and to the specific properties of the metal and alloy.